The seawater playground of gilded-era San Francisco burned to the ground in 1966.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

A massive volcanic plug is now a protected area that hosts a number of bird species.

Remants of foundations, streets, and streetcar tracks inhabit the cliffs where a landslide occurred in 1929.

This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.

Oldest building in California still in use.

Megachurch turned Catholic church comprised of 10,000 glass panes.

The site of murders and Satanic cult gatherings.

North America's first frozen mummified remains of an ice age steppe bison, the 36,000 year-old mummy named "Blue Babe."

Mind-blowing carvings and fantasy ice scenes grace the largest year-round ice environment in the world.

The king of U.S. high points towers over every other peak on the continent.